I've been playing with 7 for a few weeks now and I have to say, I'm both impressed and annoyed by it! Odd in a way, but here is the reason for such a strange dichotomy. It's notably faster than Vista and handles pretty well. The crappy PC I'm testing it on runs smoothly and is usable for my daily tasks which is terrific. It has given the box a new lease on life and the only cost has been an upgraded video card. The driver support so far has been good and everything works.
Now for the bad - I recently joined the system to my Windows Server 2008 based domain and the log on time - from boot to three finger salute and login blew out enormously. I checked a variety of things that it might have been - often I find that DNS issues cause slow downs here, but my DHCP assigned IP addresses use my 2008 server as their primary DNS server so it isn't that. The system is on a gig network, and both server and client have gig networking cards in it. At first I thought it was only initial log in problems, but I have now come to realise that it does it *every* time. As I started a deeper investigation the hard disk that the system resided on failed which throws yet another variable into the mix. I'm yet to add the system back to the domain.
After the re-install (which has worked flawlessly) the system has run very smoothly and I'm very happy with it. I look forward to further updates for Windows 7 - particularly flash which doesn't seem to work. Software I'm using successfully with it includes Microsoft Office 2007, latest Firefox and Chrome and Adobe Reader. The interface is quite nice - I have the Aero effects on my crappy PC still handles it pretty well. Turning them off does give a noticeable speed increase. I look forward to putting it onto a more powerful system and seeing what it can really do.